Choosing the Cluster Type that's Right For You - Page 3

Server clusters, like most other things in Windows 2000, are modular in nature. They are made up of nodes, groups, and resources. As you might expect, a node is simply a server that is a part of the cluster. A group is a unit of fail over. Each group contains a collection of resources, or objects that can be brought online or taken offline. A group is owned by a node, and all resources within a group run on the same node that owns the group. If any one resource within a group fails, all resources in the group will be temporarily moved to a different node until the cause of failure is resolved.

You might wonder how Windows 2000 knows how and when to move groups between nodes. It does so using something called the Quorum Resource. The Quorum Resource exists on an NTFS partition within the shared hard disk array. It is basically a collection of all the cluster's configuration information, fail-over policies, and recovery logs.

As with NLB servers, there are several different ways to configure server clusters. I'll dedicate an upcoming article to configuring NLB servers. Then, I'll continue the series with an article on configuring server clusters. These articles will touch on such issues as the various server configuration models available and how to do capacity planning for each type of server. //

Brien M. Posey is an MCSE who works as a freelance writer. His past experience includes working as the director of information systems for a national chain of health care facilities and as a network engineer for the Department of Defense. Because of the extremely high volume of e-mail that Brien receives, it's impossible for him to respond to every message, although he does read them all.